This specification relates to generating query refinements.
Internet search engines provide information about Internet accessible resources, e.g., Web pages, images, text documents, multimedia content, that are responsive to a user's search query by returning a set of search results in response to the search query. A search result includes, for example, a Uniform Resource Locator (URL) and perhaps a snippet of descriptive information for resources responsive to a search query. A search engine may also present query refinements, e.g., other queries related to the user's search query, that may be directed to what a user may consider to be relevant to the search.